Hi hi, It is much easier to deal with lists than a large number of separate objects. So the first answer to your question
> How can I apply a function to a list of variables. .. might be to convert your "list of variables" to a regular list. Instead of ... monday <- 1:3 tuesday <- 4:7 wednesday <- 8:100 ... you could have: mydays <- list(monday=1:3, tuesday=4:7, wednesday=8:100) ... and things will be a lot easier. If you happen to have a thousand of such variables in your workspace then you can convert them to a list using ... listvar=list("Monday","Tuesday","Wednesday") mylist <- lapply(listvar, get) ... but this is not always nice to you, for example, if you have variables that have the same names as some functions in base packages. Try this: a<-1 b<-2 c<-3 mean<-4 listvar <- c("a", "b", "c", "mean") lapply(listvar, get) - a safer way would be lapply(lv, get, envir=.GlobalEnv) # and for a named list, the best I can think of is: structure(lapply(lv, get, envir=.GlobalEnv), .Names=lv) And then ... > func=function(x){x[which(x<=10)]=NA} > lapply(listvar, func) do you want actually to change your variables with this? Or just to have a list with your original variables where any x[x<=10] is set to NA? In the first case you'll need to do nonstandard tricks that everyone will say you should avoid (but you can use e.g. `assign`, or macros - see `defmacro` in package gtools). In the second case you just need to take care that your function would return a sensible value. An assignment returns the value that was assigned, in this case, it is always NA but if that's not what you meant, you can try func <- function(x){ x[x<=10] <- NA; x} lapply(listvar, func) hth On Tue, Nov 8, 2011 at 6:59 PM, Ana <rrast...@gmail.com> wrote: > Hi > > Can someone help me with this? > > How can I apply a function to a list of variables. > > something like this > > > listvar=list("Monday","Tuesday","Wednesday") > func=function(x){x[which(x<=10)]=NA} > > lapply(listvar, func) > > were > Monday=[213,56,345,33,34,678,444] > Tuesday=[213,56,345,33,34,678,444] > ... > > in my case I have a neverending list of vectors. > > Thanks! > > ______________________________________________ > R-help@r-project.org mailing list > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide http://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code. > ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.